java json serialization performance

If you want to write benchmarks, use JMH. Writing high quality benchmarks isn't easy and JMH does a lot of the heavy lifting for you (although there are still a few gotchas).
If you wonder which Java Json library serializes/deserializes faster for various payload sizes, you can look at this extensive benchmark which compares a dozen of them with JMH. Fasted is dsljson, second is jackson. Gson is actually pretty slow for a 'modern' lib.

android - What is the most suitable Java data structure for representing JSON?

java - Selecting the most efficient JSON library for this use case

java - How to improve Performance in JSON parsing

java - Jackson performance of deserializing at two locations vs deserializing whole json

Jackson management for very large JSONs in Java

More results from stackoverflow.com

Discussions

The Newest Java Json Benchmark Results just dropped

Jackson performance good enough to support the bulk of use cases, and tons of support. Looks like I won’t be moving More on reddit.com

r/java

124

May 1, 2023

Actual JSON serialization benchmark for Java-APIs - Stack Overflow

I'm looking for an benchmark for different serialization APIs. All I found are outdated Posts and Articles from a year and more before. So I'm hoping that anyone could share a link to an up to date More on stackoverflow.com

stackoverflow.com

json - Java Jackson Large Object Serialization Optimization - Stack Overflow

I am using Jackson to serialize large objects about hundreds of other objects in it. This comes with the performance problems. Most of the custom Serialization class is same as "AmountAsStringSerializer" in the "JSONSerializer" class and all defined static. More on stackoverflow.com

stackoverflow.com

android - Jackson JSON Parser performance - Stack Overflow

Multiple posts on the Internet point toward Jackson as having better parsing performance than GSON, granting somewhere in the neighborhood of 20-30% speed improvement. http://rick-hightower.blogsp... More on stackoverflow.com

stackoverflow.com

Oracle

blogs.oracle.com › javamagazine › java-json-serialization-jackson

Efficient JSON serialization with Jackson and Java | javamagazine

These benefits are counterbalanced by some negatives; the biggest is that a document serialized by JSON can be quite large, which can contribute to poor performance for larger messages.

reddit.com › r/java › the newest java json benchmark results just dropped

r/java on Reddit: The Newest Java Json Benchmark Results just dropped

May 1, 2023 - Sounds a lot like avaje-jsonb which uses source code generation and can either use Jackson core under the hood or its own faster generator/parser. A relatively major performance boost that can be used that is not in Jackson is to use pre-encoded keys in deserialisation. Jackson can use pre-encoded keys for serialisation but not the other way around.

Medium

medium.com › @abhaybansal.1988 › java-json-serialization-shootout-which-library-reigns-supreme-5ffd66018fe4

Java JSON Serialization Shootout: Which Library Reigns Supreme? | by Abhay Bansal | Medium

August 30, 2025 - Fastjson/Fastjson2: Excellent overall performance, often leading or very competitive in both serialization and deserialization, especially for custom objects and higher data volumes. Fastjson2 has a notable edge in some custom object scenarios. Jackson: A consistently strong and reliable performer, usually a close second or third. A robust choice for general use. Gson: A solid, general-purpose library, though typically not the top performer in these benchmarks. org.json.JSONObject: Consistently the slowest due to its more manual approach and less optimized internal implementation for complex objects.

Apache

fory.apache.org › blog › fory_json_fastest_java_json_framework

Introducing Apache Fory™ JSON: Blazingly Fast JSON Serialization for Java | Apache Fory™

August 11, 2026 - Fory JSON's performance comes primarily from four implementation choices. Minimal temporary allocation. A ForyJson instance reuses prepared type metadata, execution state, and retained writer buffers. For most basic scalar values, the hot serialization path is effectively zero-allocation beyond the requested output: Fory writes the value directly into its output buffer instead of first converting it into a Java String.

Girija Swain

gsswain.com › 2025 › 12 › 07 › java-serialization-performance-showdown.html

Java Serialization Performance Showdown | Girija Swain

December 7, 2025 - A key, unmeasured factor in the ... the object was serialized to ~750 bytes. Text Formats (JSON, Avro JSON): Are much more verbose, resulting in a payload size of ~1220 bytes—over 60% larger!...

Baeldung

baeldung.com › home › java › core java › different serialization approaches for java

Different Serialization Approaches for Java | Baeldung

1 month ago - When speed is important for our application, Apache Thrift and Google Protocol Buffers are great candidates for serializing data. Both are more compact and quicker than XML or JSON formats. To sum up, there is often a trade-off between convenience and performance, and serialization proves no ...

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GitHub

github.com › ngs-doo › json-benchmark

GitHub - ngs-doo/json-benchmark: JSON benchmark for .NET and Java · GitHub

Gson 2.7 - "Gson is a Java library that can be used to convert Java Objects into their JSON representation" It's known issue that serialization libraries suffer from startup time, since they need to build and cache parsers for types.

Stack Overflow

stackoverflow.com › questions › 12276722 › actual-json-serialization-benchmark-for-java-apis

Actual JSON serialization benchmark for Java-APIs - Stack Overflow

Top answer

1 of 2

Here is a one benchmark.

http://code.google.com/p/thrift-protobuf-compare/wiki/Benchmarking

In this article I discuss the importance of re-cycling objects to improve serialisation times.

http://vanillajava.blogspot.co.uk/2011/10/serialization-using-bytebuffer-and.html

IMHO: JSon is one of the most difficult formats to deserialise efficiently, even harder than XML.

2 of 2

Here are two recent ones as of last week. It compares form byte[], reader, inputStream, char[], CharSequence, String, etc.

It compares Boon, Jackson, Smart JSON and GSON.

https://github.com/gatling/json-parsers-benchmark

https://github.com/RichardHightower/json-parsers-benchmark

Boon and Jackson are close on a few. At times Boon is 4x faster. Mostly Boon wins. :) GSON is better than most at I/O, but Boon does best all around (and best at I/O), and it has an index overlay mode that is even faster (look at the second set.. the index overlay puts Boon way over the top).

https://github.com/RichardHightower/boon

I am bias. :)

But gatling is not, and the results are the same. Boon is wicked fast.

Visionarysoftware

visionarysoftware.solutions › visions › java › serialization › results.html

Results of JMH Performance Comparison for Java Serialization libraries

Gson’s default serialization performs pretty competitively despite its simplistic approach. Johnzon, despite the seeming cleanliness of the code, struggles slowly in all cases with its default serialization for FiveFieldClass and TenFieldClass, losing even to Java in all cases.

GitHub

github.com › RichardHightower › json-parsers-benchmark › wiki › Serialization-Jackson-vs.-Boon-vs.-Java-Serialization

Serialization Jackson vs. Boon vs. Java Serialization · RichardHightower/json-parsers-benchmark Wiki · GitHub

April 18, 2014 - Boon JSON serialization is much faster than Jackson JSON serialization. java -jar target/microbenchmarks.jar ".*serialization.*" -wi 2 -i 3 -f 2 -t 16

Author: RichardHightower

Robert-franz

robert-franz.com › 2013 › 12 › 09 › comparing-serialization-performance

Comparing Serialization Performance | block zero

In comparsion with the standard Java serialization it’s times faster! Then there is Protobuf and ByteBuffer. The fastest is Unsafe. The difference between the fastest and the slowest almost factor 100! Even when using Json, this is four times faster than standard java serialization.

Blogger

rick-hightower.blogspot.com › 2014 › 04 › which-is-faster-java-object.html

Sleepless Dev: Which is faster Java Object Serialization (ObjectOutputStream/ObjectInputStream) or Jackson JSON serialization? The answer will surprise you.

April 18, 2014 - Groovy JSON support and the Boon JSON parser are up to 3x to 5x faster than Jackson at parsing JSON from String and char[], and 2x to 4x faster at parsing byte[]. Groovy JSON support and Boon JSON support are also faster than Jackson at encoding ...

Medium

medium.com › justeattakeaway-tech › json-serialization-libraries-performance-tests-b54cbb3cccbb

JSON Serialization Libraries Performance Tests | by Israel Abramov | Just Eat Takeaway-tech | Medium

April 18, 2021 - If memory allocation is the biggest key factor for you then SpanJson, NetJson*, System.Text.Json and Protobuf-Net should be considered. In my considerations, I am giving more weight to the data of the first two tables (Serialization and Deserialization success) because most of the serialization/deserialization actions are results with success, so these results will be the performance cost of using those libraries in our web applications most of the time.

Stack Overflow

stackoverflow.com › questions › 41286218 › java-jackson-large-object-serialization-optimization

json - Java Jackson Large Object Serialization Optimization - Stack Overflow

Stack Overflow

stackoverflow.com › questions › 26261228 › jackson-json-parser-performance

android - Jackson JSON Parser performance - Stack Overflow